Transport and Storage Apparatus for Wound Care Exudate

ABSTRACT

A device for transporting waste gases and liquid exudates from a wound. The device may include a multi lumen tubing and a connector for securing the multi lumen tubing to a fitting. The multi lumen tubing may include a double wall containment structure with a first lumen and a second lumen. The connector may include a body with a first cavity on one side, a second cavity on another side, and an interior wall located between the first cavity and the second cavity. The interior wall may form a projection in the second cavity. The projection may include an outer surface and a ledge adjacent the outer surface. The projection may cooperate with the multi lumen tubing to form a liquid-gas separator. The ledge may include a bore extending between the first cavity and the second cavity. The bore may house a gas permeable and a liquid impermeable barrier.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/095,750 filed on Dec. 22, 2014, which is incorporated by referenceherein in its entirety.

FIELD OF THE INVENTION

The present invention generally relates to wound care. Moreparticularly, this invention relates to transport and storage devicesfor waste gases and exudates related to wound care such as, negativepressure wound therapy and other treatments, including continuoustopical oxygen therapy.

BACKGROUND

Negative Pressure Wound Therapy (NPWT) may be used to treat wounds,including acute wounds, chronic wounds, pressure ulcers, and diabeticfoot ulcers. For example, a dressing may be applied to a chronic woundto form an airtight seal, and a pump may be connected via a tube to thedressing to evacuate air from the dressing and draw drainage from thewound. NPWT may accelerate wound healing by various mechanismsincluding: removal of exudate, reduction of edema, contraction of woundedges, stimulation of angiogenesis, changes in the wound edges, andproduction of granulation tissue. Nevertheless, wound treatment withNPWT may provide limited efficacy should the healing process stall orcontraindications, such as advancing infection in the wound, develop.Although oxygen delivery therapies may be used to successfully treatwounds, including wounds that have failed NPWT, a need exists for newdevices and systems that may improve patient outcomes and expand accessto patients with limited mobility or clinical support.

SUMMARY

Hence, the present invention is directed to devices for the collection,transport and storage of exudate wastes from wound care. A device fortransporting waste gases and liquid exudates from a wound may include amulti lumen tubing. The multi lumen tubing may comprise a double wallcontainment structure. The double wall containment structure may includea first wall which forms an outer containment structure for a firstlumen, the outer containment structure including a first end portion, asecond end portion, and a first longitudinal axis extending from thefirst end portion to the second end portion. The double wall containmentstructure further may include a second wall which forms a tube thatdefines a second lumen, the tube being spaced from the first wall suchthat the first and second walls are concentrically aligned about thefirst longitudinal axis, and such that the first wall and the secondwall define the first lumen. Additionally, the device may include aconnector for securing the multi lumen tubing to a fitting. Theconnector may comprise a body having a second longitudinal axis suchthat the body incudes a first end surface with a first cavity extendinginto the body from the first end surface, the first cavity being boundedradially about the second longitudinal axis by a first cavity side wall.Also, the body may include a second end surface spaced from the firstend surface along the second longitudinal axis. The second end surfacemay include a second cavity extending into the body from the second endsurface, the second cavity being bounded radially about the secondlongitudinal axis by a second cavity side wall. Moreover, the body mayinclude an interior wall located between the first cavity and the secondcavity, the interior wall forming a projection in the second cavity. Theprojection may comprise an outer surface facing the second cavity sidewall, and a ledge adjacent the baffle surface. The ledge may include abore extending between the first cavity and the second cavity. Ahydrophobic filter may be positioned in the bore such that thehydrophobic filter forms a gas permeable and a liquid impermeablebarrier between the second cavity and the first cavity.

The second cavity and the second cavity side wall may be configured anddimensioned to connect the multi lumen tubing to the connector. Thesecond cavity and the second cavity side wall may be configured anddimensioned to telescopically receive the first wall of the outercontainment structure. The outer surface of the projection, the firstwall of the double wall containment structure, and the second wall ofthe double wall containment structure may cooperate to form a passagethat fluidly connects the first lumen, the second lumen and the boreextending between the first cavity and the second cavity. The passagethat fluidly connects the first lumen, the second lumen, and the boreextending between the first cavity and the second cavity may beconfigured and dimensioned to form a liquid-gas separator such that aliquid-gas mixture being conveyed from the first lumen to the secondlumen changes flow direction abruptly to separate liquid from theliquid-gas mixture.

The ledge may extend into the second lumen. The second lumen may includea blind end. The second lumen may house absorbent material. Theabsorbent material may include one or more superabsorbent polymers.

The multi lumen tubing may be flexible. The multi lumen tubing may bedesigned to convey gases under negative pressure. The multi lumen tubingmay be designed to convey a waste gas liquid mixture from a wound. Thefirst lumen may have a first cross-section perpendicular to the firstlongitudinal axis, the first cross-section having annular shape. Thesecond lumen may have a second cross-section perpendicular to the firstlongitudinal axis, the second cross-section being of different shapethan the first cross-section. The second cross-section may be ofcircular shape.

The hydrophobic filter may include a plug of filter media. The filtermedia may be a POREX filter media. The body may be configured anddimensioned to mate with a standardized fluid fitting.

DESCRIPTION OF THE DRAWINGS

In the accompanying drawings, which form a part of the specification andare to be read in conjunction therewith and in which like referencenumerals (or designations) are used to indicate like parts in thevarious views:

FIG. 1 is a cross-sectional view of an embodiment of a dressing assemblyfor the application of negative pressure wound therapy, transdermaloxygen delivery, or combinations thereof to a wound;

FIG. 2 is a schematic diagram of an exemplary embodiment of a multilumen tubing and connector system for transporting waste gases andexudate from the dressing assembly of FIG. 1;

FIG. 3 is an exploded view of the connector system of FIG. 2;

FIG. 4 is an exploded view of a connector body and the multi lumentubing of FIG. 2;

FIG. 5 is a schematic diagram of an exemplary embodiment of a multilumen tubing and NPWT and topical oxygen delivery (TOD) apparatus forthe application of negative pressure wound therapy, transdermal oxygendelivery, or combinations thereof to a wound;

FIG. 6 is a schematic diagram of the multi lumen tubing of FIG. 5.

FIG. 7 is a schematic diagram of the multi lumen tubing of FIG. 5 with aturbulence inducing structure; and

FIG. 8 is a schematic diagram of the multi lumen tubing and insert ofFIG. 7.

DESCRIPTION

FIG. 1 shows an illustrative wound cavity 6 adjacent to intact skin 8.The wound cavity 6 includes a wound bed 10 prepared for NPWT andtransdermal oxygen flow therapy with an exemplary embodiment of adressing 12 for applying such wound care therapy. The dressing 12 mayinclude a wicking layer 14 which abuts and covers the wound bed. Thewicking layer 14 may be made from moisture-wicking synthetic fabric 16(e.g., Under Armour® or similar fabric). The wicking layer 14 may drawexudates away from the wound and aid in establishing a contiguous flowof oxygen across the wound bed. The wicking layer 14 may include anoxygen delivery manifold 18 to encourage topical delivery of oxygen tothe wound. Additionally, the wicking layer 14 may include a mixed gasand exudates removal manifold 20. This manifold may facilitatedistributed oxygen flow across the wound bed, and may promote waste gasand exudates removal from the wound. The manifolds may be placedcontralaterally within the wound bed to promote oxygen flow distributionand enhance contact time. The oxygen delivery manifold 18 may beconnected to a first length of flexible tubing 22. The first length offlexible tubing 22 may include a standardized fluid fitting 24 (e.g.,Luer Lock fitting) for connecting the other end of the flexible tubingto the oxygen supply port of a wound care device. Similarly, the wastegas and exudates removal manifold 20 may be connected to a second lengthof flexible tubing 26. The second length of flexible tubing 26 mayinclude a standardized fluid fitting 24 (e.g., Luer Lock fitting) forconnecting the other end of the second length of flexible tubing to anintermediate waste canister or directly to the vacuum supply port of awound care device. The tubing 22, 26 may be made from a polymericmaterial suitable for use in hospital applications. Suitable materialsfor use in the tubing include, but are not limited to, silicone,polyethylene, polypropylene, polyurethane and various otherthermoplastics.

The dressing 12 further may include an absorbent layer 28 above themanifold and wicking layer. The absorbent layer 28 may hold exudatesthat are transported through the wicking layer. The absorbent layer 28may provide structural support for the wound, the manifold and the firstand second lengths of tubing. Additionally, the absorbent layer 28 mayprovide a protective barrier for the wound bed against physical traumaor microorganisms. In one embodiment, the absorbent layer 28 may begauze. In another embodiment, the absorbent layer 28 may be polyurethanefoam.

The dressing 12 further may include a semi-occlusive layer 30. Thesemi-occlusive layer 30 may be a sheet of transparent film. The sheet oftransparent film may include adhesive on one side to help create an airtight seal around the perimeter of the wound bed. The semi-occlusivelayer 30 may include penetrations 32 for passage of the first and secondlengths of tubing 22, 26. The penetrations 32 may be located above thedressing manifolds. Sealant may be applied around the penetration andthe flexible tubing to form air tight seals. In one embodiment, thesheet of film may be a Tegaderm® dressing manufactured by 3M.

During therapy, the oxygen port on the dressing (i.e., the first lengthof tubing 22) may be connected via flexible tubing or other conduit toan oxygen source for delivering oxygen to the wound. The vacuum port onthe dressing (i.e., the second length of tubing 26) may be connected viaflexible tubing or other conduit to a vacuum source for applyingnegative pressure to the wound. For example, oxygen may be delivered tothe wound bed at an average pressure of approximately 760 mmHg; whereas,the applied negative pressure may range from approximately 50 mmHg toapproximately 200 mmHg. The net partial pressure of oxygen on the woundsurface may be in the range of 560 mmHg to 710 mmHg.

A liquid trap may be disposed between the vacuum source and the tubingwhich connects the vacuum source to the vacuum port of the dressing. Theliquid trap may be located inside or outside of the mechanical pumphousing. A liquid trap, however, also may be situated on the dischargeside of the mechanical pump. A liquid trap further may include baffles,absorbent material, valves, conduit, and fittings such that the liquidtrap contains exudates that are discharged from the wound dressingwithout leakage independent of the orientation of the device. The liquidtrap may operate based on mechanical principles or chemical-mechanicalprinciples.

The dressing 12 for applying transdermal oxygen therapy and/or negativepressure wound therapy to a wound may use a multi lumen tubing andconnector system in addition to or in place of the tubing. FIG. 2 showsa multi lumen tubing 34 and connector system 36 for use in the dressingassembly of FIG. 1.

As shown in FIG. 2, the multi lumen tubing 34 may include a double wallcontainment structure. A first wall 38 may form an outer wall of thedouble wall containment structure. A second wall 40 may form aconcentric inner wall of the double wall containment structure. Thedouble wall containment structure may define two conduits 42, 44. Afirst conduit 42 may be bounded by the interior sidewall of the outerwall and the exterior sidewall of the inner wall. The first conduit 42may have a cross section of annular shape. The second conduit 44 may bebounded by the interior sidewall of the inner wall, and may possess across section of circular shape. The second conduit 44 further mayinclude an end wall 46 that seals one end 48 of the second conduit. Theopposite end 50 of the multi lumen tubing 34 may be received in aconnector body.

Referring to FIG. 2, FIG. 3 and FIG. 4, the connector body 52 mayinclude a first end 54 for mechanically connecting to a mating port 56,as well as a second end 62 which may be configured and dimensioned toreceive the opposite end 50 of the double wall containment structure. Asshown in FIG. 2 and FIG. 3, the connector body 52 may be configured anddimensioned to fluidly connect the opposite end 50 of the double wallcontainment structure to the mating port 56. The connector body 54 mayinclude a nozzle 60 which docks with the mating port 56 to fluidlyconnect the multi lumen tubing 34 to the mating port. As shown in FIG. 2and FIG. 4, the second end 62 of the connector further may include aliquid-gas separator 64. The liquid-gas separator 64 may be integral tothe connector body. Alternatively, the liquid gas separator may beformed in conjunction with the multi lumen tubing or in combination withother parts.

Referring to FIG. 2, the liquid-gas separator 64 may connect the annularconduit 42 to the connector body outlet 58 and the inner conduit 44 viaone or more passages 68 that include at least one abrupt change indirection. The passage 68 may be configured and dimensioned to separatewaste gases and liquids from the annular conduit 42 such that when awaste gas and liquid mixture flows through the one or more passages 68,the direction of flow changes abruptly, and inertia causes liquids tocontinue in one direction of flow (e.g., downward into the innerconduit), but allows the gas component (which more readily assumes thechange of flow direction) to flow in another direction (e.g., toward theconnector body outlet) away from the liquid mist particles.

Thus, movement of waste gas liquid mixture 74 within the second end 62of the connector body 52 may result in separation of liquid mist 78 fromthe gas component 76 because gases may more readily assume a change offlow direction and will flow away from the liquid mist particles. Theliquid mist 78 may coalesce on a surface 70 or fall into a liquidcontainment area 72 (e.g., inner conduit area). Separation of liquid andgas further may be affected with either a sudden increase or decrease ingas velocity. For instance, with a decrease in velocity, the higherinertia of the liquid mist may carry it forward and away from the gas.The liquid further may coalesce on some surface and gravitate to theliquid section of the separator. By contrast, with an increase in gasvelocity, the higher inertia of the liquid generally may cause the gasto move away from the liquid, and the liquid may fall to the liquidsection of the separator.

Referring to FIG. 2, FIG. 3 and FIG. 4, the connector body 52 mayinclude a hydrophobic filter 90. The hydrophobic filter 90 may bepositioned to intercept the flow of waste gas liquid mixture 74 betweenthe second end 62 and the first end 54 of the connector body. Thehydrophobic filter 90 may be a gas permeable and liquid impermeablematerial. For instance, the hydrophobic filter 90 may be a plugfabricated from fiber or porous materials, such as polyethylene (PE),high-density polyethylene (HDPE) and polypropylene (PP)). For example,POREX Pipette Filter Media manufactured by Porex Technologies, 500Bohannon Road, Fairburn, Ga. 30213 may be suitable for use as ahydrophobic filter media in the connector body. The hydrophobic filter90 may be positioned in the outlet 58 and/or the nozzle 60 of theconnector body. Indeed, the connector body 52 may be molded around thehydrophobic filter 90. Accordingly, the connector body 52 may bespecifically configured to enhance gas-liquid separation.

Referring to FIG. 3, a vacuum source (e.g., a mechanical pump intake)from a wound care device may be connected to the mating port 56 of theconnector system 36. As shown in FIG. 2, the first end 54 of theconnector may be connected to the mating port 56. The second end 62 ofthe connector may be connected to the multi lumen tubing 34. The firstconduit 42 of the multi lumen tubing 34 may be in fluid communicationwith a wound or dressing headspace. The second conduit 44 may be closed46 at the wound end 48 and open at the connector body 52. As suction isapplied to the first conduit 42, waste gases and exudates may be drawninto the annular conduit 42. When the flow of waste gas and liquidmixture 74 reaches the connector 52, the flow may be forced to changedirection, causing the liquid component 78 of the mixture to fall intothe second conduit 44 where it may be collected and stored. The secondconduit 44 further may contain absorbent material 84 to help retain theexudate and keep it from being pulled in by the pump. The absorbentmaterial, without limitation, may be a foam structure, a sponge, achemical material that absorbs liquids, or a combination thereof. Forexample, the absorbant material may be one or more superabsorbentpolymers (SAPs). The cross sectional area of the first conduit 42 (e.g.,the annular conduit) may be smaller than the cross sectional area of thesecond conduit 44 (e.g., the circular conduit). This generalconfiguration may be advantageous because a smaller flow area may affecthigher waste gases and exudates flow rates that may promote exudateremoval and transport away from the wound. Conversely, a larger crosssectional area of the central conduit 44 may be advantageous because agreater volume for collecting and storing liquid waste may be availableand because the larger diameter may affect lower flow rates of wastegases which may prevent the vacuum from removing separated exudate. Forexample, 40″ of conduit with a 3.6 mm inner diameter would provideapproximately 10 cc of collection volume.

FIG. 5 shows a schematic diagram of another multi lumen tubing 34′ andNPWT and topical oxygen delivery (TOD) apparatus 100 for the applicationof negative pressure wound therapy, transdermal oxygen delivery, orcombinations thereof to a wound. The apparatus 100 may include a woundcare device 92 that includes an oxygen supply port 94 and a vaccumsupply port 96. The apparatus 100 further may include a dressing 12. Theoxygen delivery manifold 18 of the dressing 12 may be connected to theoxygen supply port 94 by a first length of tubing 22. The wound exudatesremoval manifold 20 of the dressing 12 may be connected to the vacuumsupply port 96 by a multi lumen tubing 34′.

Referring to FIG. 5 and FIG. 6, the first wall 38 of the multi lumentubing 34′ may be liquid and gas impermeable, but the second wall 40 maybe porous. For example, the second wall 40 may be formed from agenerally liquid impermeable and gas permeable material but may includeopenings 82 which fluidly connect the second conduit 44 and the firstconduit 42. An absorbent material 84 may be placed in or on the firstconduit 42. The absorbent material 84 may be similar to the absorbentmaterials used in diapers. A hydrophobic filter 90 may be positioned atthe discharge end 50 of the multi lumen tubing 34′ to prevent liquidfrom directly exiting the multi lumen tubing. In use, waste gas liquidmixture 74 may flow through the openings 82 and contact absorbentmaterial 84 in the first conduit. The absorbent material(s) 84 mayremove liquid 78 from the waste gas liquid mixture flow 74. To promotephase separation and contact of the waste gas liquid mixture with theabsorbent materials in the first conduit, an insert 86 may be placed inthe second conduit 44 to intercept or disrupt waste gas liquid mixtureflow 74.

Referring to FIG. 7 and FIG. 8, a structure or insert 86 may bepositioned in the second conduit 44 such that the insert 86 changes theflow path of waste gas liquid mixture 74 and directs the liquid waste 78toward absorbent material 84 in the first conduit 42. In one example,the insert 86 may include a spiral insert or segment. In use,turbulence, such as vortices may be produced by the interaction of thewaste gas liquid flow and insert may enhance phase separation. Thepresence of a hydrophobic filter 90 further may enhance phase separationand prevent liquid waste from leaving the multi lumen tubing. Thestructure or insert 86 may be integrally formed as part of the secondconduit 44. Accordingly, a turbulence inducing structure(s), such as aspiral shape and/or an arrangement of one or more baffles may be moldedin as part of the inner wall of the second conduit. For example, withoutlimitation, a turbulence inducing structure may be coextruded with thesecond conduit or the second conduit may be molded over the turbulenceinducing structure.

The foregoing devices for the collection, transport and containment ofexudate wastes from wound care may be used with a wound care device anda wound dressing assembly to provide negative pressure wound therapy,transdermal oxygen therapy, or combinations thereof to a wound. Theseconsumables may be replaced on an as needed basis. Thus, the dressing12, tubing 22, 26, multi lumen tubing(s) 34, 34′, and connector body 52described herein may be available in individually sealed sterilepackaging.

While it has been illustrated and described what at present areconsidered to be embodiments of the present invention, it will beunderstood by those skilled in the art that various changes andmodifications may be made, and equivalents may be substituted forelements thereof without departing from the true scope of the invention.For example, in some clinical applications it may be efficacious toplace one or more segments of a multi lumen tubing between the secondlength of tubing and a third length of tubing connected to a vacuumsource of a wound care device. Similarly, it may be to useful to placeone or more segments of a multi lumen tubing between the first length oftubing and a fourth length of tubing connected to a therapeutic gassupply (e.g., oxygen) of a wound care device. Additionally, featuresand/or elements from any embodiment may be used singly or in combinationwith other embodiments. Therefore, it is intended that this inventionnot be limited to the particular embodiments disclosed herein, but thatit have the full scope defined by the language of the following claims,and equivalents thereof.

What is claimed is:
 1. A device for transporting waste gases and liquidexudates from a wound comprising: a multi lumen tubing comprising, adouble wall containment structure which comprises a first wall whichforms an outer containment structure for a first lumen, the outercontainment structure including a first end portion, a second endportion, and a first longitudinal axis extending from the first endportion to the second end portion, and a second wall which forms a tubethat defines a second lumen, the tube being spaced from the first wallsuch that the first and second walls are concentrically aligned aboutthe first longitudinal axis, and such that the first wall and the secondwall define the first lumen; a connector for securing the multi lumentubing to a fitting, the connector comprising a body having a secondlongitudinal axis such that the body comprises a first end surface whichcomprises a first cavity extending into the body from the first endsurface, the first cavity being bounded radially about the secondlongitudinal axis by a first cavity side wall, a second end surfacespaced from the first end surface along the second longitudinal axis,the second end surface comprises a second cavity extending into the bodyfrom the second end surface, the second cavity being bounded radiallyabout the second longitudinal axis by a second cavity side wall, aninterior wall located between the first cavity and the second cavity,the interior wall forming a projection in the second cavity, theprojection comprising an outer surface facing the second cavity sidewall, and a ledge adjacent the outer surface, the ledge comprising abore extending between the first cavity and the second cavity, and ahydrophobic filter positioned in the bore such that the hydrophobicfilter forms a gas permeable and a liquid impermeable barrier betweenthe second cavity and the first cavity.
 2. The device of claim 1,wherein the second cavity and the second cavity side wall are configuredand dimensioned to connect the multi lumen tubing to the connector. 3.The device of claim 2, wherein the second cavity and the second cavityside wall are configured and dimensioned to telescopically receive thefirst wall of the outer containment structure.
 4. The device of claim 3,wherein the outer surface of the projection, the first wall of thedouble wall containment structure, and the second wall of the doublewall containment structure cooperate to form a passage that fluidlyconnects the first lumen, the second lumen and the bore extendingbetween the first cavity and the second cavity.
 5. The device of claim4, wherein the passage that fluidly connects the first lumen, the secondlumen, and the bore extending between the first cavity and the secondcavity is configured and dimensioned to form a liquid-gas separator suchthat a liquid-gas mixture being conveyed from the first lumen to thesecond lumen changes flow direction abruptly to separate liquid from theliquid-gas mixture.
 6. The device of claim 5, wherein the ledge extendsinto the second lumen.
 7. The device of claim 1, wherein the secondlumen comprises a blind end.
 8. The device of claim 1, wherein thesecond lumen houses absorbent material.
 9. The device of claim 8,wherein the absorbent material comprises one or more superabsorbentpolymers.
 10. The device of claim 1, wherein the multi lumen tubing isflexible.
 11. The device of claim 10, wherein the multi lumen tubing isdesigned to convey gases under negative pressure.
 12. The device ofclaim 11, wherein the multi lumen tubing is designed to convey a wastegas liquid mixture from a wound.
 13. The device of claim 1, wherein thefirst lumen has a first cross-section perpendicular to the firstlongitudinal axis, the first cross-section having annular shape.
 14. Thedevice of claim 13, wherein the second lumen has a second cross-sectionperpendicular to the first longitudinal axis, the second cross-sectionbeing of different shape than the first cross-section.
 15. The device ofclaim 14, wherein the second cross-section has circular shape.
 16. Thedevice of claim 1, wherein the hydrophobic filter comprises a plug offilter media.
 17. The device of claim 16, wherein the filter media is aPOREX filter media.
 18. The device of claim 1, wherein the body isconfigured and dimensioned to mate with a standardized fluid fitting.